Boiler



Jan.'8, 1935. J c, HOBBS 1,986,821

BOILER Original Filed Jan 13, 1928 2 Sheets-Sheet ld. 24%, INVENTOR WIKM ATTORNEYS Jan. 8, 1935.

.J. C. HOBBS BOILER Original Filed Jan. 13, 1928 2 Sheets-Sheet 2 0 O O O O O O O O. O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O OOOOOOOOOOOOO OOO OOOOOOOOOOOOOOOO O O O O O O O O O O O O O O O O O 13 OOOOOOOOOOOOOOOOOv OOOOOOOOOOOOO O OOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOO OOOOOOOOOOQOOOOOO OOOOOOOOOOOOOOOOO N mhw OOOOOOOOOOOOOQOO .mv

INVENTOR $14 ATTORNEYS Patented Jan. 8; 1935 nven'tion relates-to a water tube boiler which som'e o'f lthe tubes are arranged above theiboiler fui nace to form a slagscreen. "The invention will be understood from" the? following .1 description in'fconnection with the accompanying drawings in whichw. Fig. T 1"is a vertical section thrbugh a illustrative@embodiment of L the in-.

ventiony -Figa -2 is "a$section along the line 2-2 of Fig. 1, and Fig. 3 is a section similar to Fig. 2 'showing amodification i I In the drawings; reference. character 1 indicates the frontwvalliof ai furnacethat is provided with a; bridge-wall 2 were reari One of the sidewalls is' shown at 3 in Fi'gsfl2 and f 31:: The furnace is provided with stoker' 4; and a 1 wat'er'tube boiler of a wen-known type with inclined water tubes In rated E a's being located above 1 the furnace. boilercomprises" a plurality of longitu dlnal 5f'thatare'supported by "means 'of heat dto the i upper ends of downta'ke headers s atid ui'atake --hea.ders' 9 whichare, fin! .turn,.fconnected by a bank: of"parallel inclined tubesIO.

new" en-(is et the headers 8 and 9 are conhected y means dfnipples Hand 12 .to the upper ends of header e 13 and 14which arefin turn, bon'helcted by bank of parallel inclined tubes 15 iiownt'akei and "uptake 'headersxareishown as vert allys xten ingg and -the tubes connecting 30 thes "aders which are disposed abovethe furnace oWnfias being disposed in rows Sp =a1'i rt vfe i'callyand with the tubes in any on disposed in aihorizontallyq inclined plane,

ekeept las hereinafter" noted. 'For the nsakewof convenience oi f expressio'n and. to define a relation to soine datum;thelvarious parts will be hereinthus,'-b'y reference tothe vertical headers and ubes: make with I respect to: the vertidaT-and horizontalsare-not essential parts of ,the 'invention! t 1 i The memos-tr e of thetubes 15 has the ends selecte tubes,; shown :in -Fig; -2 as-being alte'- ate-t bes", bent so that the majorp'ortions he'se elected-tubeslie' some distance below o-the dther 'tubes'in-the row; The l "nds f theseselected-tubesare bent at two pints n andfi lll toprovide a portion 191: that is substantially horizontal, so that the tubes will 'iirain"intd -the headers l3; and the upperends w the tubes -are bent as indicated at 20, so that the ends of t'he bent tubes enter their iheaders 33110 the same horizontal lines as .the ends of 1th -refria'ining straight tubes in the: row. 1

r 1, 1;j9 ss,s21 j p ,YBOILER James-o. Hobbs, Painesville, Ohio ,Appli catienJanuary 13, 1928, Serial; N3J24a411 August 23,1933 "1's ClaimsU-"i-( 1:122-298) straps? 6-= from I-bea'ms' 7. The "drums: are coni or zon l -althoughthe angles *lwhichthe. ac i ad t t p enterandstrik tub of the tubes in the lowermost row of the tube Theabbve cohstructioh provides an' arrange- 1 mentinwhich thetubes in one row, for example the lowermost row in the bank, have their end portions disposed in a common-horizontally inclinedplanexand in which the selected tubes have the majoryportions thereof disposed outof that 5 plane andin another plane parallel thereto, these majorportions being connected to their end portions by means of reverse bends In the embodiment shown in Fig. 1, the plane occupied by the portions 16 of the selected tubes is one which passes below the lowermost ends of theheaders, as will be plainly seen from an inspection of Fig. 1. .T It will likewise be noted that since the portion 19 of a selected tube ie-horizontal, andsince the same selected tube is'in each instance connected to the-downtake header at the lowest point of thetube, there can be no downward flow of any fluid passing from the downtake headerto the uptake header.

.Nipplest21 connect the lower ends of the headers 13 to the mud drum 22 and bafiles 23 and 24 direct the hot products of combustion from thefurnace across the banks of tubes 10 and In the modification shown in Fig. 3, thelower headers 14 are made straight along their lower. portions instead of sinuous as in Fig. 2} and some of the rows of tubes 15' have the tubes in the rows spaced apart horizontally twice as far asthe corresponding tubes in rows 15. The ends of the bottom row of tubes all enter the headers along the same horizontal lines and alternate tubes 16' are bent downwardly in-the same way asfabove described in connection with the tubesjin Fig. 2. Inthismodification, some of the tubes '16 areomitted, the-third tube of each group of three being, omitted to provide -triangula'rly shaped higher in the bank than is possible with-the usual construction.

- The way in which the tubes of thelowermost row. are spaced in Fig; 3 w'ouldapply'to the tube arrangement shown in 2 by omitting certain bank shown inFig. 2. p i i By bending the selectedtubes as above described, from one row into an adjoining row wider spaces are, left between'tubes immediately above the furnace, thusforming a slag screen, so that 5 the trouble due to the spaces" between the tubes being bridged by'slag collecting upon the tubes is obviatedand'th'e opening of the passage to the next row of tubes above permits the absorption of more radiant heat. Also theopening of the 5 entrance to the first row of tubes permits the velocity of' the gases entering to be decreased. When some of the tubes are omitted, as shown in Fig. 3, the radiant heat is enabled to strike tubes at a higher level in the tube bank and in some cases to strike a given tube from two directions through wider lanes than is possible with the ordinary arrangement. When the radiant heat strikes,-tubes;,at, -a .higher level, theamountaof radiantfheat that is thrown back intercepted in part and absorbed by some of the tubes which come nearer the furnace.

slag adheres to the under sides of the tubes in the lowermost row. When this occursin the,.orbeingwarallehto the plane of said first-named dinary arrangement the slag becomes heated and reflects radiant heat...back' intol' the-{furnace and at the same time prevents the full absor ption of the radiant heat'by the lowermostetubeseby forminga heat resisting coating on the tubes.

- Withfthe lowermost tubes bent; andv spacedin the way described, the slag which; accumulates son the -lowermost vlinaof tubes, will have .a, lesser effect 'inthrowingthe heatiback ,intothe-furnace than with the; :ordinary' arrangement. of 'tube bankwherepthextubesare-not so spaced.v s, g 5 Likewise, ;,the invention is one which cannbe readily applied either to aboiler :already place 0! to, a rboiler which .isbeing. installed new. For examplaif it, isidesired to provide aslag-zscreen for a;boiler whic-his already in p1ace, without;materially changing existing structuraitwill be seen thatimy inventionyprovides a ready. wayv of doing so; i-fiselectedtubes ina-certain'roware to be displaced from the gplaneof that row; .then the oldaholes in the headers whichreoeived'the tubes replaced :by thexselectedztubes, and which holes of :coursezare in, that same, plane, maybe :used to receive the; end portions of the selectedtubes. Therefore; very; little change in existingstructure isqnecessary. j-=At the same time,-the;invention mayrbegreadily used with new installations. i

:hileI have shown the invention as-embodied in a specific form, it is to be understood that yari ous changes in {details may bemade without -depart-ingirom, the scope of the-invention,yas-.defined byethe appended: claims. 7 J=.Iclaimr- J s s l.1,-I-n: a water tube boiler, uptake anddowntake headerswabank of inclined tubes connected to saidheaders, and extending; across the upper, portion of, the boiler furnace, thealternatetubes of theglowermost rows being bent at their: ends seas tqimakathe main portion of. the alternate tubes inlth f lowermost row come below the remainder o f'the' tubes in.;the lowermostrow, s mezor said alt ate'ibent tubes being omitted. f a'wat'er 't' beboiler, uptakelandjdowntake ers', "a; bank of inclinedtubes connected to lowermost row being bentand the main portions thereof lying" below the other tubes oflthat row, and each thirdtube ofsaidalternate tubes being omitted. v .v

3. In a water tube boiler, verticallyextending uptake'and downtake headers connected-by tubes extending above 1a. furnace, the lowermost. tubes being connectedv to said headers closely-adjacent the-lower: ends of the headers, end. portions :ofgall of 'sa'iid' lowermost tubes. being arranged'JiIL-a' row and" theirnajor, portions of SBIG CtGdJOIIGS'iOf said lowermost tubes being arranged ir'ranotherjower row -.'and being :joined tto's their .end ".portionszby reifei se'rbehdsssaid lower IOW'IhGiIIgQGiSDQSGG. in

sreverse bends, said lower row being disposed in a. This arrangement is particularly effective whe e plane extending below the lower end of the headers to which said end portions are connected and row. N

5; ln a wvater tubezboiler, vertically extending *uptakeand downtake headers connected by tubes -;extendin g above a furnace, the lowermost tubes being connected to said headers closely adjacent the'iowemends; of; the headerssthezendportiansof all: or saidrlowermost: tubes. atibotlrsiendsnoftthe tubes beingarranged ima row andzthemaj'onportions :iofj: selected: onesnofssaid lowemnost-inubes beingtzarranged in lanothers;lowerrrownandebemg joinedgtd-theirend portionsiby; reversezbendspsaid lower: row; being idisposed vinva:plane-.aextending below, the [lowerend of: therheaders totwhichsaid endiportions are connected.

6. In a water tube boilemvertically extending.

uptakeian'd. downtakerheaders:connected byetubes extendingnabove r-a furnace .the tlowemnosmtubes being :connected .to: said-1 headersicloselysaddaeent theiowen ends of ithesheaders; the: end-mentions ofi'all of saidlowermost tubesiatzbothiendssofi-the tubes being=arranged imarowaandtheunajor portionszof; selected tones:ofisaiddowermosutubessbeing' :arranged j inizanother flower; rowsaand ebeing joinedtotheiriendcportionsibymeverseebendspsaid lowererow;:being adisposed;:insavplaneeextending belowsthe lowen-end 0t thesheaders toswhicmsaid endzportionsiare; connected andebeingmuwllehto the plane ofisaidznirstenamed row. 7 H

hna (water tube: boiler nptakezand downtake upwandly.iromzther downtake r'headen-to thesp atakeaheadernaaslagascreemcomprising certaimof saidtub'es havingmheiopposite end pertionsdhereofidisposed ashorizontallyuinclined; planegthe maj or 13 art-of: the; length: ofca diube initenmediate its-sendnportionszbeingdisplaced;out 0ft saidiplane and Joined;to;-.saidzendyportionsbbwnevesse :bends, the; bendsibeing soizformediiand iarmnged that the lowest;points thebenttubesrareioeated attheir connectionsgto:,Ithe downtakerheadersa; water: tube :;bo'iler, suptakesandtdown- .take-sheaders-s connected iby..;tubes,:rsaidr. tubes!- rtendingrlupwardly fromfitherdownitakerheadercto the uptake-:headerga slag=screenzcomprisingmem tain'zofr saidrtubes: :h avingi the-ioppositeeendgpore tions thereof disposed in a horizontallyeinclined plane,:ithezmajorgparta;of.-.the1-length=iofizaitube intermediate its-endi P -1 displaced out :ofcsaidg plane-:but: substantially para-Hell theeeto and" j cine dto; saidnend; portionsbyr TBVEEISGLbBRdS,,

the bends :being son-formed 3811-? substantially avoid; any downward .:-.fio,w 201E193? fluid -p through: a tube: fromrtherdowntake :header :totthe uptakeheader. v

9.:- Iniawva-ter tube boilergsuptakeaandidowntske headers.connected:bytubesnsaidrtubesrextending disposed in. a zzhorizontally inclined-mime, time upwardlyi-fromrthei downtakezdieadem-toiithe npj r intermediate its end portions being disposed below lowest points in the bent tubes their connection to the downtake headers.

12. In a water tube boiler, uptake and downtake headers connected by tubes, said tubes extending upwardly from the downtake header to the uptake header, aslag screen comprising cerformed as to substantially avoid any downward major part of the length of a tube intermediate its opposite end portions being displaced out of said plane and joined to the end portion in said plane by a reverse bend, said bend being so flow of a fluid passing through a tube from the downtake header to the uptake header.

10. In a water tube boiler, uptake and downtakeheaders connected by tubes, said tubes extending upwardly from the downtake header to the uptake header, a slag screen comprising certain of saidtubes havingthe opposite end portions thereof disposed in a horizontally inclined plane, the major part ofthe'length of a tube intermediate its end portions being disposed below said plane and joined to said end portions by reverse bends, the bends being so formed as to substantially avoid any downward flow o f,a fluid passing through a tube from the downtake header to the uptake header.

11. In a water tube boiler, uptake and down-,

take headers connected by tubes,said tubes extending upwardlyfrom the downtake header to the uptake header, a slag screencomprising certain of said tubes having the opposite end por-' tions thereof disposed in a horizontally inclined. plane, the major part of the length of a tube said plane but substantially parallel thereto and joined to said end portions by reverse bends, the bends being so formed and arranged that the are located at tain of said tubes having end portions at one end thereof disposed in ahorizontally inclined plane, the major part of the length of a tube intermediate its opposite end portions being disposed below said plane and joined to the end portions in said plane by areverse bend, said bend being so formed and arranged that the lowest point in said tube is located at its connection to the downy take header.

13. In a water tube boiler, uptake and downtake headers connectedby tubes, said tubes extending upwardly from the downtake header to the uptakeheader and arranged in horizontally extending rows 'forming a bank of tubes, the majority of saidrows being spaced apart verticallyand entering holes in said headers, which [holes are spaced apart horizontally, one of said rowsbeing formed by some only of the tubes in an adjoining row displaced for the major parts adjoining row and connected to said major parts by reverse bends, whereby the horizontal spacing of the tubes in the rows from which and to which said tubes are displaced is increased without changing the arrangement of holes in said headers, r

JAMES C. HOBBS.

v oftheinlengths from said adjoining row but hav- 1 ing-their end portionsentered in'holes in said 

